In a wide variety of situations and circumstances, it is convenient to provide a plurality of strategically located audible signals which are used for a wide variety of purposes frequently including one or more of the following: background music; paging; announcements; advertisements; and a variety of alarms. Furthermore, any of these audio signals may be applied to less than the total plurality of audio devices. As an example, such as system might be used in a large department store to provide background music in a least selected areas during part of the time when the system is not otherwise engaged. At some time it might be appropriate to have an announcement made within a specific department, or on one floor, concerning an event or conditions of interest only to people within that department or on that floor. At such times, it is desirable to be able to provide signals through less than all of the audio devices. At other times, a situation may exist wherein it is desirable to produce a paging, announcement or alarm signal on all of the audio devices and do so with priority over the background music and/or more local alarms, announcements or signals. Furthermore, a situation can readily be envisioned wherein it is desired to produce a general page or alarm, from some principal control point such as the main office; and at other times to produce such general page or alarm signals from another area such as a guard station; and at other times to produce paging or alarm signals generated from an alternate guard area or an annex building. Other situations and needs for announcements and/or signals from other areas may be readily envisioned. The system may also find utility in high rise buildings.
It will be seen that such systems may be rather complex and that in order to prevent confusion which would result if more than one message, or signal, was being applied to the audio devices simultaneously, it is desirable to have the system arranged with a predetermined hierarchy or priority in such manner that in times of emergency the system can be commandeered and used by the highest priority transmitting area.
U.S. Pat. No. 3,656,158 issued Apr. 11, 1972 to Harry C. Goodwater, described a low voltage audio fire alarm system fully integrated into a paging and music speaker system. This system is particularly directed to supervision of the system and components. However, it does disclose a system providing paging, background music and alarm signals through an audio system. Various manufacturers provide a wide variety of paging, alarm and background music systems. One such producer, the Federal Signal Corporation, does provide a system that permits the use of two command units in one system. However, two signals may be present on the signal line should both command unit be keyed simultaneously. Modification can permit use of two command units although use of more than two command units can result in their destruction if keyed simultaneously.
It is an object of the present invention to provide a new and improved paging and alarm system with signals capable of being originated from any one of a variety of locations.
It is another object of the system to be able to control less than all of the audio devices from remote locations.
It another object of the invention to be able to control selected audio devices locally.
It is another object of the invention to provide a control console which may control all of the audio devices.
It is a more specific object of the invention to provide a control console which can provide audio signals to remote audio devices and override audio signals applied to any or all of the audio devices from remote control stations.
It is another object of the invention to provide a plurality of control consoles any one of which may provide audio signals to the remote audio stations with priority over locally generated signals.
It is another object of the invention to provide a system including a plurality of control consoles which are identical but interconnected in a hierarchy system.
It is another object of the invention to provide an alarm signalling, paging and background system wherein the background music has the lowest priority with increasing priorities in the following named sequence: a signal generated from a remote source and normally directed to less than all of the audio devices; a priority signal generated from the same remote station and having a priority over the previously named signal; a tone from one of the control consoles; a priority tone from one of the control consoles; a tone manually selected from a keyboard at one of the consoles; a test mode condition and voice paging.
It is another object of the invention to be able to provide the automatic tone, the automatic priority tone, the manually operated tone, the test mode and the paging from any one of the plurality of control consoles.
It is another object of the invention to arrange the control consoles in a predetermined hierarchy so that any action at any of the control consoles has priority over the action of a lesser priority console.
It will not be here attempted to set forth and indicate all of the various objects and advantages incident to the invention, and other objects and advantages will be referred to, or else will become apparent from the following description.